^{page 677 note *} The second determinant is incorrectly printed in the original.

^{page 686 note *} Cayley's first memoir on quantics was presented to the Royal Society of London on 20th April, and this paper on the notation of matrices is the first of five which appeared together in Crelle's Journal with the date 24th May affixed by the author.

^{page 690 note *} Brioschi does not note the independent importance of his second set of equations, which may be condensed into

and which, when r, s=1, 1 and n=3, is

This, however, may be viewed also as a case of Sylvester's theorem, namely, where the first row of P is 1,0, 0.

^{page 701 note *} In using the notation ║ ║ he is not more explicit than its author, Cayley. If it were explained that

stands for

it would rediely follow that the statement

was short for

and that

was short for